Because it is very rare.
Salt hasn't gold.
Yes, they did trade there gold for salt.
Yes, gold is an expensive metal.
what is difference in a gold ring and rock salt
No one person. Gold is rare and useful- the rarity makes it expensive. If there was gold sitting around everywhere, it would not be expensive.
Gold and salt
They traded mostly gold and salt
Because most countries did not have salt mines or the ability to extract it. Most ancient peoples relied on sea evaporation or trade, which made it a very rare and expensive commodity.
Gold is tremendously more expensive than titanium.
Mail traded Gold and Salt with neighboring countries.
As far as I know Spanish gold has been the most expensive. Perhaps not the rarest but the most expensive
Because salt is not expensive is not necessary to recycle.